Why this script not removing the whole gui but leaving screen black?

This is the script thats in the play button, it fades away but it leaves the screen black and you cant see anything.

script.Parent.MouseButton1Click:connect(function()
	local a = 1
	script.Parent.Parent.Frame.BackgroundTransparency = a
	script.Parent.Parent.Frame.Visible = true
	for i = 1,30 do
		script.Parent.Parent.Frame.BackgroundTransparency = a
		a = a - 0.05
		wait()
	end
	script.Parent.Parent.Frame.BackgroundTransparency = 0
	local b = script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound.Volume
	repeat
		wait(0.3)
		script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound.Volume = b
		b = b - 0.05
	until script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound.Volume == 0
	wait(1)
	script.Parent.Parent.Parent.Parent.TeamColor = BrickColor.new("White")
	script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound:Stop()
	script.Parent.Parent.Parent.Parent:LoadCharacter()
end)

script.Parent.MouseButton1Click:connect(function()
    script.Parent.Parent.Frame.BackgroundTransparency = 0
    script.Parent.Parent.Frame.Visible = true
    for i = 1,30 do
        script.Parent.Parent.Frame.BackgroundTransparency = i / 30
        wait()
    end
    script.Parent.Parent.Frame.BackgroundTransparency = 1
    local b = script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound.Volume
    repeat
        wait(0.3)
        script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound.Volume = b
        b = b - 0.05
    until script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound.Volume == 0
    wait(1)
    script.Parent.Parent.Parent.Parent.TeamColor = BrickColor.new("White")
    script.Parent.Parent.Parent.Parent.Backpack.CamFix.Sound:Stop()
    script.Parent.Parent.Parent.Parent:LoadCharacter()
end)

What I did is made it so it would add to the transparency instead of subtracting from it